1. Field of the Invention
The present invention relates to the field of model driven design in general, and specifically, to the field of data integration using client-specified model.
2. Description of the Background Art
In recent years, the volume of data stored in databases has increased dramatically, along with the need to share existing data under a single query interface. One solution to these problems is data integration. Data integration is the process of providing a client with a unified way of accessing data residing on multiple source systems. However, prior art approaches of data integration have numerous problems that remain unresolved.
One prior art approach of data integration is data warehousing. Data warehousing involves Extracting data from different databases, Translating the heterogeneous data to a uniform schema, and then Loading the data into a single warehouse repository (i.e., “the ETL process”). The data from the different databases can then be accessed by a client using a single or unified query interface. However, this prior art approach is time consuming and computationally expensive.
The data warehousing approach has numerous additional problems. One problem is that the different data architectures are tightly coupled because the data resides in a single repository at query time. As a result, it is difficult to maintain the “freshness” of the data stored in the warehouse without performing multiple ETL processes. For example, assume that data from databases A, B and C are processed and stored in Warehouse Z. Now assume that databases A, B and C are updated with new data. Because the architecture of the data warehousing model is tightly coupled, this update will not be realized at Warehouse Z unless a new ETL process in initiated. Another problem with the data warehousing approach is that the warehouse repository can be difficult to construct in web environments because the designer frequently only has access to a query interface instead of all the information on the databases. Yet another problem with the data warehousing approach is these systems do not allow the client to specify a data model for the data stored in the warehouse.